1. Field
Apparatuses and methods consistent with the disclosure provided herein relate to a switch mode power supply, and more particularly, to a switch mode power supply which reduces standby power consumption.
2. Description of the Related Art
As energy regulation on displays increases, methods for reducing standby power consumption by switch mode power supply (SMPS) has gained attention.
As generally known, the SMPS generates good quality electricity free of ripples by switching the switching devices in accordance with a signal of modulated pulse width so that electronic devices operate efficiently. The SMPS can be designed in small sizes and with light weights and high efficiency.
A general SMPS circuit is illustrated in FIG. 1. Particularly in Europe, in order to satisfy harmonic standards, the SMPS generally employs a power factor collection (PFC) circuit 110. Similar to turning on a switch of a display device using a remote controller or the like, a transistor 131 of a power on/off control circuit 130 turns on in normal state to supply power Vcc to a PFC controller 111, thus switching on the secondary output and the screen of the display device.
Referring to FIG. 2, when a user does not watch television (TV), the TV turns to standby mode and when the TV is on standby mode, power supply to the PFC circuit 110 is cut using a standby controller 121 of a standby circuit 120 since the PFC circuit 110 does not need to operate in this state, so the standby circuit 120 alone is driven. That is, the standby power consumption is reduced by reducing the number of the constant power-consuming devices.
However, as illustrated in FIG. 2, there is a limit to the reduction of standby power consumption since some circuit components still consume constant power in standby mode.